The political world is once again buzzing about evangelical Christians. Former senator Rick Santorum’s near-victory in the Iowa caucuses and his ascent in the ranks of Republican presidential contenders have fueled this new fervor, which is leading to the same tired debates and conversations that we’ve heard about evangelicals for a generation now.

Santorum’s rise in Iowa supposedly occurred because he talked about “social issues” — abortion, same-sex marriage and the breakdown of the nuclear family. But so did virtually all the other candidates. So what is it that resonates with this influential voting bloc, that propels evangelical support for one conservative candidate over another?

If you really want to understand evangelicals in America today, fix your eyes on Mile High Stadium in Denver this Sunday afternoon, when the Denver Broncos and the Pittsburgh Steelers will meet in the wild-card round of the NFL playoffs. The game will feature two star quarterbacks whose contrasting stories — one of zeal, one of redemption — reveal more about the nature, power and persistence of American evangelicalism than a caucus or primary ever could